ignite-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Denis Magda <dma...@apache.org>
Subject Re: New SQL execution engine
Date Fri, 27 Sep 2019 16:10:30 GMT
Ignite mates, let me try to move the discussion in a constructive way. It
looks like we set a wrong context from the very beginning.

Before proposing this idea to the community, some of us were
discussing/researching the topic in different groups (the one need to think
it through first before even suggesting to consider changes of this
magnitude). The day has come to share this idea with the whole community
and outline the next actions. But (!) nobody is 100% sure that that's the
right decision. Thus, this will be an *experiment*, some of our community
members will be developing a *prototype* and only based on the prototype
outcomes we shall make a final decision. Igor, Roman, Ivan, Andrey, hope
that nothing has changed and we're on the same page here.

Many technical and architectural reasons that justify this project have
been shared but let me throw in my perspective. There is nothing wrong with
H2, that was the right choice for that time.  Thanks to H2 and Ignite SQL
APIs, our project is used across hundreds of deployments who are
accelerating relational databases or use Ignite as a system of records.
However, these days many more companies are migrating to *distributed*
databases that speak SQL. For instance, if a couple of years ago 1 out of
10 use cases needed support for multi-joins queries or queries with
subselects or efficient memory usage then today there are 5 out of 10 use
cases of this kind; in the foreseeable future, it will be a 10 out of 10.
So, the evolution is in progress -- the relational world goes distributed,
it became exhaustive for both Ignite SQL maintainers and experts who help
to tune it for production usage to keep pace with the evolution mostly due
to the H2-dependency. Thus, Ignite SQL has to evolve and has to be ready to
face the future reality.

Luckily, we don't need to rush and don't have the right to rush because
hundreds existing users have already trusted their production environments
to Ignite SQL and we need to roll out changes with such a big impact
carefully. So, I'm excited that Roman, Igor, Ivan, Andrey stepped in and
agreed to be the first contributors who will be *experimenting* with the
new SQL engine. Let's support them; let's connect them with Apache Calcite
community and see how this story evolves.  Folks, please keep the community
aware of the progress, let us know when help is needed, some of us will be
ready to support with development once you create a solid foundation for
the prototype.

-
Denis


On Fri, Sep 27, 2019 at 1:45 AM Igor Seliverstov <gvvinblade@apache.org>
wrote:

> Hi Igniters!
>
> As you might know currently we have many open issues relating to current
> H2 based engine and its execution flow.
>
> Some of them are critical (like impossibility to execute particular
> queries), some of them are majors (like impossibility to execute particular
> queries without pre-preparation your data to have a collocation) and many
> minors.
>
> Most of the issues cannot be solved without whole engine redesign.
>
> So, here the proposal:
> https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=130028084
>
> I'll appreciate if you share your thoughts on top of that.
>
> Regards,
> Igor
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message